System and method for controlling interface between PBX and ATM multiplexing transmitter
AssigneeFujitsu Limited
InventorsReiko Norizuki, Ryuji Hyodo, Susumu Eda, Kenji Tanaka, Katsumi Oomuro, Osamu Sekihata, Hiroyuki Hatta, Tetsuo Nishino
Life of this patent
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Abstract
In a congestion control system for an interface between a PBX and an ATM multiplexing transmission unit connected to a network via an ATM transmission line, a congestion detecting unit detects a congested state in which the ATM transmission line is congested with traffic. A control unit inhibits a call from the PBX from being sent to the ATM transmission line via the ATM multiplexing transmission unit when the congestion detecting unit detects the congested state.
Claims17
A congestion control system for controlling congestion in an interface between a PBX (Private Branch Exchange) and an ATM (Asynchronous Transfer Mode) multiplexing transmission unit which is connected to an ATM network via an ATM transmission line, said congestion control system comprising:
- congestion detecting means positioned in said ATM multiplexing transmission unit, for detecting a congested state in which the ATM transmission line is congested with traffic;
- and
- control means, coupled to said congestion detecting means, for congestion control operation such that when the congested state is detected by the congestion detecting means said control means produces a pseudo busy state which is detected at said PBX and inhibits a call from the PBX from being sent to the ATM transmission line via the ATM multiplexing transmission unit in response to said pseudo busy state.
A congestion control method for controlling congestion in an interface between a PBX (Private Branch Exchange) and an ATM (Asynchronous Transfer Mode) multiplexing transmission unit which is connected to an ATM network via an ATM transmission line, said congestion control method comprising the steps of:
- (a) detecting a congested state in which the ATM transmission line is congested with traffic by said ATM multiplexing transmission unit;
- and
- (b) controlling congestion such that when a congested state is detected a pseudo busy state is created, and detecting said pseudo busy state at said PBX and inhibiting a call from the PBX from being sent to the ATM transmission line via the ATM multiplexing transmission unit in response to said pseudo busy state.
A congestion control method for controlling congestion in an interface between a PBX (Private Branch Exchange) and an ATM (Asynchronous Transfer Mode) multiplexing transmission unit which is connected to an ATM network via an ATM transmission line, said congestion control method comprising the steps of:
- (a) detecting a congested state in which the ATM transmission line is congested with traffic by said ATM multiplexing transmission unit;
- and
- (b) controlling congestion such that when a congested state is detected a call is inhibited from the PBX from being sent to the ATM transmission line via the ATM multiplexing transmission unit, wherein:
- a two-wire transmission line connects the PBX and the ATM multiplexing transmission unit to each other;
- and
- said step (b) comprises the step of setting two wires of said two-wire transmission line to polarities corresponding to a busy state.
An ATM (Asynchronous Transfer Mode) transmission unit connected to a telephone exchange through a synchronous transfer mode channel, for interfacing the synchronous transfer mode channel to an ATM network, the ATM transmission unit comprising:
- congestion detecting means for detecting a congested state of the ATM network:
- control means, in response to information of the congested state from the congestion detecting means, for producing a pseudo busy state and notifying the telephone exchange that the synchronous transfer mode channel is to be treated as being in a busy state.
A transmission unit for converting data of a telephone call in a synchronous transfer mode from a telephone exchange into a plurality of fixed length cells each having a header field and an information field provided with the data, and for transmitting a fixed length cell to a network, the transmission unit comprising:
- a controller which detects a congested state of the network and in response to said detected state produces a pseudo busy state;
- and
- an interface for regulating, in response to information indicative of the congested state and the pseudo busy state from the controller, a telephone call through a synchronous transfer mode channel, said interface notifying the telephone exchange that the synchronous transfer mode channel is to be treated as being in a busy state.
A congestion control method for an ATM (Asynchronous Transfer Mode) transmission unit, connected to a telephone exchange through a synchronous transfer mode channel, for interfacing the synchronous transfer mode channel to an ATM network, the method comprising the steps of:
- detecting a congested state of the ATM network;
- producing a pseudo busy state in response to said congested state;
- notifying the telephone exchange that the synchronous transfer mode channel is to be treated as being in a busy state, in response to information indicative of the pseudo busy state and the congested state of the ATM network;
- and
- regulating a telephone call through the synchronous transfer mode channel in response to said pseudo busy state.
A communication system comprising:
- a telephone exchange;
- and
- a transmission unit converting data of a telephone call in a synchronous transfer mode from the telephone exchange into a plurality of fixed length cells each having a header field and an information field provided with the data, and transmitting a fixed length cell to a network, the transmission unit including:
- a controller which detects a congested state of the network and in response to said detected state produces a pseudo busy state;
- and
- an interface for regulating, in response to information indicative of the congested state and the pseudo busy state from the controller, a telephone call through a synchronous transfer mode channel, said interface notifying the telephone exchange that the synchronous transfer mode channel is to be treated as being in a busy state.
A congestion control method for a transmission unit converting data of a telephone call in a synchronous transfer mode from the telephone exchange into a plurality of fixed length cells each having a header field and an information field provided with the data, and transmitting a fixed length cell to a network, the method comprising the steps of:
- detecting a congested state of the network;
- producing a pseudo busy state in response to said congested state;
- notifying the telephone exchange that the synchronous transfer mode channel is to be treated as being in a busy state, in response to information indicative of the pseudo busy state and the congested state of the network;
- and
- regulating a telephone call through the synchronous transfer mode channel in response to said pseudo busy state.
Dependencies are inferred from the claim text.